Door hinge

ABSTRACT

A hinge for a motor vehicle door allows the door to be displaced with respect to a door pillar in a transverse movement combined with a pivoting movement by means of a four-joint mechanism that has a support arm and a control rod, both of which are hinged to the door and the door pillar. The support arm has a base support arm, at least one support arm element that can be detached from the base support arm and that has two hinge lugs supported on an extremity of the support arm, and means for interlinking the base support arm and the support arm element. The support arm element can be adjusted relative to the support arm through an axis that extends through the tangent plane of the base support arm and the support arm element by rotating them around a swiveling axis that is perpendicular to the tangent plane.

FIELD OF THE INVENTION

The invention relates to a door coupling according to the preamble ofclaim 1 for a door of a motor vehicle, in which the door can bedisplaced with respect to a door pillar in a transverse movementcombined with a pivoting movement by means of a four-joint mechanism,the four-joint mechanism having a supporting arm connected in anarticulated manner to the door and in an articulated manner to the doorpillar and a control rod connected in an articulated manner to the doorand in an articulated manner to the door pillar, the supporting armbeing fastened in an articulated manner with regard to the door andpillar at in each case two gudgeons assigned to the end regions of thesupporting arm.

BACKGROUND OF THE INVENTION

U.S. Pat. No. 3,275,370 describes a door which is coupled to a motorvehicle via a four-joint mechanism and in which a plate-like supportingarm is designed in the form of a rectangle arranged rearward and havingfour gudgeons which are arranged in the region of the corners, whichdefine an axis inclined with respect to the vertical on each side of thesupporting arm, while a control rod in the frontal region of the doorcontrols the displacement movement of the door. In the case of the knownmechanism, the hinge leaves which, together with said gudgeons, definethe other part of the joints are fastened to the door assembly parts,the door and door pillar, without any possibility of fine adjustment inorder to correct installation and manufacturing tolerances.

U.S. Pat. No. 3,095,600 describes a door which is coupled to a motorvehicle via a four-joint mechanism and in which an upper and a lowersupporting arm having respectively laterally offset joints, and acontrol rod are provided, in order to arrange the door in a pivotablemanner on the vehicle. In the case of imprecise fastening, this type ofcoupling causes at least a stiff type of coupling. All possible freedomsin the fastening of the door are required for the coupling functioningto some extent, so that asymmetrical arrangements, occurring on accountof dimensional, manufacturing and installation tolerances, of the doorin the corresponding opening of the vehicle body cannot be corrected.

EP-A-0 569 403 describes a door which is coupled to a motor vehicle viaa four-joint mechanism and in which the four-joint mechanism is formedin a four-joint hinge whose hinge brackets on the door and on the pillareach have a coupling to a joint of a supporting arm and a joint of acontrol rod, the supporting arm furthermore having joints which aredefined by individual hinges in alignment with the supporting-arm jointswhich are provided on the hinge brackets. The supporting arm iscircumscribed within its gudgeons by a rectangle. In order for the doorto be adjustable, the control rod is divided into two halves which canbe mutually fixed by screw bolts interacting via holes, as a result ofwhich, for example, the rearward joint of the supporting arm adopts adifferent position relative to the frontal joint of the control rod, andthus has the theoretical possibility of changing the position of thedoor in the vehicle body about the vertical, in which case there areonly two alternatives here. However, asymmetrical arrangements,occurring on account of dimensional, manufacturing and installationtolerances, of the door in the opening of the vehicle body cannot becorrected sufficiently precisely.

U.S. Pat. No. 4,665,586 describes a door which is coupled to a motorvehicle via a four-joint mechanism, in which an upper and a lowerfour-joint mechanism are each formed from a control rod and from acommon, plate-like supporting arm, there being no possibility at all ofcorrecting the orientation of the door in the vehicle body.

During installation of a motor vehicle door, the door has to be adjustedin its position with respect to the vehicle body in the x-, y- andz-direction. In this case, the x-direction stands for the direction oftravel, y for the horizontal direction transversely with respect to x,and z for the vertical direction transversely with respect to x. In thecase of a pivot-out door hinge, during the adjustment of the door withrespect to the vehicle body a defined setting of the supporting arm ofthe hinge on the interior door molding also has to take place, so thatthe part of the interior door molding which is fitted on the supportingarm can be fixed in place in a positionally correct manner with respectto the dashboard etc. This adjustment requirement greatly reduces theadjustment options in the mounting of the door carcass onto the hinge.In the case of single-hinged pivot hinges, the adjustment in order tocompensate for an angular offset between the screw-down surfaces on thedoor and on the door pillar can take place by determining the y- andz-coordinates. In the case of the pivot-out door hinge, this adjustmentoption is used up by the necessity of adjusting the supporting arm withrespect to the interior door molding. Therefore, in the case of apivot-out door hinge, an adjustment by rotating about the x-axis isadditionally required. Moreover, for tolerance reasons, when installingthe door it may be necessary, in the case of a multi-joint door hinge,to compensate for an angular offset between the screw down surfaces ofthe hinge and door panel in order to fix the positioned door onto thehinge. Such compensation can only be corrected by twisting the hingeleaf. This adjustment can take place only by changing the distancebetween the coupling axes of the control rod on the door and doorpillar. The known solutions for changing the length of the control rodare very complicated both to produce and to install.

SUMMARY OF THE INVENTION

It is the object of the invention to provide a door coupling thatenables the door position in the vehicle body to be influenced in asimple and effective manner. The door can be displaced with respect to adoor pillar in a transverse movement combined with a pivoting movementby means of a four-joint mechanism, the four-joint mechanism having asupporting arm connected in an articulated manner to the door and in anarticulated manner to the door pillar and a control rod connected in anarticulated manner to the door and in an articulated manner to the doorpillar, the supporting arm being fastened in an articulated manner withregard to the door and pillar at in each case two gudgeons assigned tothe end regions of the supporting arm.

This object is achieved for the door coupling in that the supporting armhas a base supporting arm and at least one supporting arm part that canbe detached from said base supporting arm and comprises the two gudgeonsprovided at one end of the supporting arm, and means for the mutualfastening of the base supporting arm and supporting arm part, and inthat an axis passing through the tangent plane of the base supportingarm and supporting arm part allows adjustment of the supporting arm partwith respect to the base supporting arm by mutual twisting around apivot axis which is perpendicular with respect to the tangent plane.

The door coupling according to the invention has a supporting arm whichcan be divided into a base supporting arm and at least one supportingarm part which can be detached from said base supporting arm andcomprises the two gudgeons provided on one side of the supporting arm,the base supporting arm and supporting arm part expediently having flatsides which face each other and define a tangent plane which guides atthe same time to a pivoting movement of the supporting arm part relativeto the base supporting arm in the manner of a stop. The base supportingarm and supporting arm part are mutually clamped together by means forthe mutual fastening, preferably screws or the like, these means beingof releasable design in order to permit mutual twisting of thesupporting arm part and base supporting arm around a pivot axis which isperpendicular with respect to the tangent plane. The pivot axis isdefined by an axis passing through the base supporting arm andsupporting arm part, said axis possibly not having the same orientationas the pivot axis, in which case the pivot axis is definedperpendicularly with respect to the tangent surfaces by the location atwhich the axis passes through. It is therefore possible, for example, toprovide just one pin protruding out of one of the tangent surfaces inorder to define the pivot axis, while the fastening at other points isprovided by means of a screw connection or the like.

One particular advantage of the door coupling according to the inventionis that the pivoting of the supporting arm part and base supporting armrelative to each other about relatively small angles enables theposition of the door in a recess, formed for this purpose, in thevehicle body to be corrected essentially around the x-axis, whichcorresponds to the direction of travel in the case of motor vehicles.This enables manufacturing and installation tolerances in the fitting ofthe door, which tolerances lead to a visually unattractive asymmetry ortilting relative to the vehicle body, to be corrected in a particularlysimple and efficient manner, a correction, particularly in the case of afour-joint mechanism which defines the pivoting-out movement of thedoor, at the stop points of the hinge parts on the door or door pillarbeing made more difficult by the fact that the determination of theposition relative to the interior door molding uses up the known pathsof adjustment.

In contrast, the door coupling according to the invention enablesreadjustment of a door which has already been fastened, in that screwsare provided, preferably on the rearward supporting arm part, saidscrews enabling the supporting arm part to be detached and enabledaround the pivot axis in order to correct the position of the dooraround an axis essentially parallel to the horizontal.

The tangent plane of the base supporting arm and supporting arm part isexpediently not only passed through by a central or eccentric screw fordefining the pivot axis, but furthermore also by further fixing and/orguide elements which are displaced on a circular path around the pivotaxis in a radius corresponding to this distance from the pivot axis. Forthis purpose, the fixing and/or guide element, which is preferablydesigned as a screw, is screwed into one of the two parts—the basesupporting arm and supporting arm part, while a slot, which also has alittle vertical play, is provided in the other of the two parts in orderto enable the screw shank to undergo, within the slot, a displacementcorresponding to a short circular segment. As an alternative to a slothaving vertical play, it is also possible to shape the slot tocorrespond to the circular segment and to reduce the play radiallycorresponding to the circular segment. This last variant has theadvantage that the base supporting arm is effectively prevented fromdropping during the pivoting on account of the vertical play of thesupporting arm part.

The tangent plane is to be understood as being a plane in the widestsense, i.e. it is not required for the tangent plane to spatiallycoincide with a surface. Rather, it is possible for the tangent plane tocomprise a plurality of sections, for example a displacement sectionwhich is laterally offset with respect to that section at which themeans for fastening the base supporting arm and supporting arm part passthrough the tangent plane. The tangent plane could therefore, forexample, have a dome shape which, in the case of a symmetrical design,would readily permit the pivoting movement, for example. Furthermore,the tangent plane could be formed from axially offset circular sectionswhich would likewise permit pivoting.

In the case of the arrangement according to the invention as afour-joint mechanism, the supporting arm serves essentially to transmitthe load from, in particular, large and therefore heavy doors onto themotor vehicle and, in particular, onto its door pillar which is arrangedin the region of the A-post. For this purpose, the supporting arm isformed in the manner of a plate body in whose four corner regions thegudgeons for the coupling to the door and to the pillar are formed. Thesupporting arm part is expediently fastened detachably on that side ofthe base supporting arm which faces the door, since it is particularlyreadily accessible there for adjusting the orientation with respect tothe base supporting arm. However, it is also possible, as an alternativethereto or in addition thereto, to provide a supporting arm part on thefrontal side of the supporting arm, which side is coupled to the doorpillar, as a result of which, in a manner which is similar and scarcelychanged in outcome, the orientation of the door in the recess left freein the vehicle body can be influenced by rotation around the x-axis.However, it will, as a rule, be sufficient to provide just a two-partdesign of the supporting arm.

It should be noted that the supporting arm part, the two supporting-armgudgeons being formed integrally on it, connects in respect of theiralignment and spacing the two gudgeons in the manner of a strip and thusprovides the supporting arm part to form an integral part to become amass-produced product which can therefore be positioned without anyoutlay on adjustment, with the result that even by means of a four-jointmechanism the door coupling according to the invention obtains anadjustability (which is otherwise not present) of the position of thedoor around the x-axis.

A significant advantage of the two- or multi-part design of thesupporting arm also resides in the more economical possibility ofproducing the base supporting arm from an extruded profile, in which theregion between the gudgeon portion bearing the gudgeons is produced asan independent supporting arm part and is not obtained as a costly wasteof material. In addition, the base supporting arm can be produced costeffectively by extrusion, as a result of which the mechanical furtherprocessing in order to expose the gudgeon portion is additionallydispensed with.

According to a particularly preferred development of the invention, thecontrol rod is of single-piece design and with regard to the door orpillar is coupled to a bearing plate to which a corresponding gudgeon ofthe supporting arm, preferably the lower gudgeon, is also coupled, wherethe end remote from the abovementioned side of the control rod iscoupled to a hinge part which can be fastened in a manner enabling it tobe displaced jointly with and in the direction of the control rodrelative to a corresponding hinge part assigned to gudgeon of thesupporting arm. The hinge part of the supporting arm and the hinge partof the control rod can be fastened to a door assembly part, door or doorpillar, using the same screws, and this connection is hence at the sametime a connection of the two door hinges, as a result of which thefour-joint mechanism is defined in the four-joint hinge defined by thismeans. It is alternatively possible, with the same outcome, to fastenthe hinge part of the control rod to the hinge part of the supportingarm and to fasten one of the two hinge parts to the door assembly part,door or door pillar, since by fastening the two hinge parts to eachother the joint axes of the control rod and supporting arm are definedrelative to each other, so that a defined four-joint hinge is formed bythis means.

A particular feature of this design is that the two hinge parts can notonly be connected together, but, moreover, the connection can also bedisplaced in the direction of the control rod, which has the consequencethat the relative position of the two joint axes with respect to eachother can be changed, a change in the distance between the two jointaxes in the closed position of the door having the consequence ofenabling said door to pivot around an axis running essentiallyvertically.

By providing the possibility of mutual displacement, which expedientlyis to take place in an infinitely variable manner, a particularlyprecise and sensitive correction of an offset of the motor vehicle doorin the corresponding recess of the vehicle body is possible, in whichcase, as a function of the increase or reduction in the distance betweenthe two joint axes, the vehicle door is pivoted around an essentiallyvertical axis in the direction of its rearward edge or the direction ofits front edge, if it is presumed that the control rod is engagingfurther forward than the supporting arm.

The relative displacement of the two hinge parts can take place in aparticularly simple and expedient manner by a slot running essentiallyin the direction of the x-axis (with the door closed) being formed in atleast one of the two hinge parts, a customary screw/nut combinationbeing passed through said slot and, when the desired position isreached, being tightened in order to finally fix the two door hinges inplace. There is virtually self-centering when the door is fitted.

According to an alternative embodiment, it is possible to ensure thealignment of the vehicle door, in particular the rotation about thevertical, by the fact that the supporting arm and control rod arecoupled with regard to the door and/or pillar to hinge parts which arenot connected to each other and can be fastened to the correspondingdoor assembly part, as a result of which the adjustability is providedin a manner known per se by slots, for example in the region of thesupporting arm part or hinge part, with acceptance of an increasedoutlay on installation.

According to a variant to be formed in a simple manner, the four-jointmechanism, which is designed as a four-joint hinge, can also be coupledto a rigid bearing plate as a four-joint hinge if the control rod isthen divided and the two parts of the control rod, relative to eachother, lead to a lengthening or shortening of the control rod, with thesame outcome of precision adjustment as is achieved by pivoting around avertical axis. The lengthening can be obtained, for example, byspindle-nut systems or by mutual latching positions of the dividedcontrol rod.

Further advantages and features of the invention emerge from thedependent claims and from the following description.

The invention will be explained in greater detail below using anexemplary embodiment with reference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a perspective view of a preferred exemplary embodiment of adoor coupling according to the invention.

FIG. 2 shows a perspective view of the door end of the supporting arm ofthe coupling from FIG. 1.

FIG. 3 shows a partially cutaway view through the supporting arm alongthe line III—III from FIG. 2.

FIG. 4 shows a perspective view of a further preferred exemplaryembodiment of a door coupling according to the invention.

FIG. 5 shows a plan view of the door coupling from FIG. 4.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows, in a perspective illustration, a door coupling which isdenoted by 1 and pivotably arranges a door 2, which is indicated by adash-dotted line, on a door pillar 3, likewise indicated by adash-dotted line. The door coupling 1 is undertaken by a four-jointmechanism, the bars of which are, on the one hand, a supporting arm 4and, on the other hand, a control rod 5. The supporting arm 4 and thecontrol rod 5 are coupled in an articulated manner via correspondinghinge parts to the door pillar 3, on the one hand, and to the door 2, onthe other hand.

The supporting arm 4 is of plate-like design and defines in its interiora hollow space 6 in which ribs or the like, which divide the hollowspace into a number of chambers, can be provided in order to increasethe stiffening. The cavity 6 is expediently designed such that it isopen upward and downward and thereby opens access to the interior regionof the supporting arm 4. In its corner regions, the supporting arm 4 hasin each case two door pillar gudgeons 7 a, 7 b and two door gudgeons 14a, 14 b, said gudgeons being intended for coupling to hinge partscorrespondingly fastened to the door pillar 3 and to the door 2. Thegudgeons are provided in the vicinity of the outer corners of thesupporting arm 4, the supporting arm 4 running in a plane arrangedessentially vertically.

The door pillar gudgeons 7 a and 7 b are respectively formed in thelower region and in the upper region of that corner of the narrow sideof the supporting arm 4 which faces the door pillar 3, the gudgeon 7 bbeing coupled in a known manner to a hinge part 8 and the gudgeon 7 abeing coupled in a known manner to a hinge part 9. The hinge parts 8, 9are fastened to the door pillar 3 in a known manner by means of a screwconnection and holes 10 provided for this purpose in the hinge parts 8and 9. The door pillar end of the control rod 5 is also coupled to thehinge part 9, so that the hinge part 9 has two joints having a fixeddistance from each other.

The supporting arm 4 is divided into a base supporting arm 4 a and asupporting arm part 4 b, the base supporting arm 4 a and supporting armpart 4 b butting against each other along a common tangent plane 11 andbeing held with respect to each other. The base supporting arm 4 a is ofintegral design with the gudgeon portions bearing the gudgeons 7 a, 7 b,while the supporting arm part 4 b for its part connects thesingle-reverse action joints, on which the gudgeons 14 a, 14 b definingthe coupling to hinge parts 12, 13 fastened to the door 2 are arranged,via a strip of narrow design in between them. The hinge parts 12, 13 aredesigned to have two wings and have holes 15 which pass through theirwings and by means of which they can be connected to the door 2 directlyor via an intermediate element, for example in the form of a boredspacer.

As can also be seen better in FIG. 2 and 3, the tangent plane 11, whichmay be both a solid and a perforated surface, is passed through by ascrew 16 which is provided in the corresponding holes of the basesupporting arm 4 a and supporting arm part 4 b, is arranged accessiblyon the outside of the supporting arm 4 and is secured by a nut which isaccessible in the hollow space 6. As an alternative, it is also possibleto provide, for example, the hole remote from the screw head with athread.

It can be seen that the screw 16 runs perpendicularly with respect tothe tangent plane 11 and that the screw axis 16 a runs essentiallyperpendicularly with respect to the tangent plane 11. The screw axis 16a therefore coincides with a rotational axis around the shank of thescrew 16 of the supporting arm part 4 b around the base supporting arm 4a when in the region of the tangent plane 11, by releasing the screws 17a, 17 b provided for fixing the two parts 4 a, 4 b in place, a gapbetween the supporting arm part 4 b and base supporting arm 4 a, whichpermits pivoting, is released. In this connection, the screws 17 a, bnot only form fastening elements, but also guide elements which aredefined in the manner of a cam by means of a hole, which is designed asa slot 18 and corresponds to a cam path, in that end surface of the basesupporting arm 4 a which faces the supporting arm part 4 b. It has to beunderstood that that end surface of the base supporting arm 4 a which atthe same time defines a stop for the supporting arm part 4 b is formedat least as a flat wall section in these regions in which the slots 18are formed. Those regions of the end surface of the base supporting arm4 a which are not passed through by screws 17 do not necessarily have tohave the end wall being closed by the material of the base supportingarm.

It can be seen that even in the case in which the screw makes use of aslope and does not run perpendicularly with respect to the tangent plane11, or in the case where the tangent plane 11 does not form atwo-dimensional surface, the pivot axis 16 a lies in the perpendicularwith respect to the boundary surface 11. It would therefore be possible,instead of the screw 16, to form a snug-fitting shank which protrudesout of the boundary surface 11 of the one part and passes through acorresponding hole of the other part, in which case the shank axis doesnot necessarily have to coincide with the perpendicular of the tangentplane. It can furthermore be seen that the screw 16 is not situatedcentrally between the screws 17 a, 17 b, but rather is situatedeccentrically with respect to a central position, which is advantageousfor certain applications, although it is arranged in the vicinity of thecentral position. The position of the screw 16, the axis 16 a of whichdefines the pivot axis in the present case, is defined with regard tothe dimensions of the door 2, the screw axis 16 a in a first approachrunning approximately at the height of a horizontal alignment axis ofthe door 2, for the adjustment of which the relative adjustability, asexplained below in detail, of the supporting arm part 4 b and basesupporting arm 4 a can advantageously be used.

It can be seen in particular from FIG. 2 that the screws 17 a, 17 b areinserted into corresponding threads of those gudgeon portions of thesupporting arm part 4 b which bear the gudgeons 14 a, 14 b, it beingpossible instead also to secure them by a nut outside the gudgeonportions. The connection in the region of the gudgeon portions enablesthe connection of the base supporting arm 4 a and supporting arm part 4b to be particularly strong. However, it is advantageously also possibleto move the screws 17 a, 17 b closer to the screw 16 in order thereby toreduce the amount of displacement, caused by the pivoting around theaxis 16 a, along a circular segment corresponding to the distance fromthe screw 16 and defining a radius of the circle.

It can be seen in particular in FIG. 3 that the slots 18 not onlyconstitute a hole which is elongated with respect to the shank diameterof the screws 17 a, 17 b, but also the height of the slots is enlargedwith respect to the shank diameter, as a result of which it isexpediently possible for the screws 17 a, 17 b to execute a rotationalmovement in the slots 18, said movement comprising displacementcomponents in two dimensions in accordance with trigonometricalregularities.

The door end of the control rod 5 is coupled to a two-wing hinge part 19which can be fastened to the door 2 via slotted holes 20. The hinge part12 and the hinge part 19 define a fitting state of the control rod 5 andsupporting arm 4 enabling displacement in the direction of the long slotaxis of the slot 20, the fastening of hinge parts using slots havingbeen proved in practice and division of the control rod 5 thereforebecoming superfluous. By means of relative displacement of the hingeparts 12 and 19 with respect to each other along the shanks of thescrews or bolts, which shanks pass through the holes 15 and the slottedholes 20, the holes 15 holding the screws in a virtually play-freemanner in the present exemplary embodiment, it is possible to adjust thedistance between the door joints of the control rod 5 and supporting arm4 to a limited extent, thereby essentially enabling displacement of thevehicle door 2, which is fastened to the door parts 13, 12, 19, around avertical axis, so that the position of the door 2 in the vehicle bodycan be corrected.

In the present exemplary embodiment of the door coupling 1 according tothe invention, in order to adjust the position of a motor vehicle door 2two degrees of freedom can now advantageously be used in order tocorrect the position of the door 2, said door otherwise not fittingcentrally and therefore in a visually pleasing manner due to machiningand manufacturing tolerances, even though the four-joint mechanism ofthe coupling 1 is defined by a four-joint hinge 9, 5, 4, 12/19 and wouldnot in itself permit such changes. By pivoting around the axis 16 a ofthe screw 16, the door 2 can be aligned about an axis correspondingessentially to the x-axis of the vehicle (direction of travel), and bydisplacement along the slot 20 the vehicle door 2 can be pivoted aboutthe z-axis (vertical). It should be taken into consideration here thaton account of the specific requirements of the door coupling 1 the axes16 a and the joint axes of the door joints of the supporting arm 4 andof the control rod 5 often do not coincide in an ideally typical mannerwith the x- and z-axes of the vehicle in the closed state of the door,for example because the transverse movement combined with the pivotingmovement is intended to execute a path in space. Even in these cases,adjustment of the position of the door is possible because the twoadjustment options enable, in an iterative process, those door positionsto be adjusted in which the corresponding components of the adjustmentmake possible an optimum alignment of the position of the door 2additively around the x- and around the y-axis.

In the exemplary embodiment, the hinge parts 12 and 19 are connected toeach other via in each case their two hinge leaves which are to befastened to the door and are passed through by a common bolt. It is tobe noted that it is readily possible to connect, for example, only theleft hinge wing of the hinge part 19 with the left hinge wing of thehinge part 12 and then optionally to connect one of the two right hingewings of the hinge part 12 or the hinge part 19 to the door 2, theconnection to the supporting arm 4 being expediently selected for staticreasons.

FIGS. 4 and 5 show a further exemplary embodiment of a door couplingaccording to the invention. The same reference numbers as in FIGS. 1 to3 denote the same parts here.

The door coupling 1′ which is shown in FIGS. 4 and 5 likewise has asupporting arm 4 and a control rod 5′ which connect a door 2, indicatedby dashed-dotted lines, to a door pillar 3, indicated by dashed-dottedlines, in the manner of a four-joint mechanism in such a manner that atransverse movement, combined with a pivoting movement, of the door 2relative to the door pillar 3 is made possible.

The supporting arm 4 does not differ from the supporting arm 4 fromFIGS. 1 to 3 in terms of structure and action, and in contrast to theprevious exemplary embodiment is fastened by means of its hinge part 12directly to the vehicle door 2 without a connection to the control rod5′. The door pillar hinge part 9′ just has one joint to which thegudgeon 7 a of the supporting arm 4 is coupled.

The control rod 5′ is connected in an articulated manner to the doorpillar 3 and the door 2 via a hinge part 9 a, with regard to the doorpillar, and via a hinge part 19′, with regard to the door. The controlrod 5′ and the supporting arm 4 therefore no longer form a four-jointhinge, but define a four-joint mechanism together with the rigidconnecting door 2 and pillar 3 and the corresponding hinge parts 8/9′/9a′ and 13/12/19′, it being possible for the distance between the doorjoint axes of the supporting arm 4 and control rod 5′ to be adjusted bycorresponding slots in the door, as a result of which the pivoting ofthe door 2 about the z-axis can be realized in a simple manner with anincreased outlay on installation. The adjustment of the door 2 aroundthe z-axis by twisting the supporting arm part 4 b relative to the basesupporting arm 4 a can therefore be undertaken in the manner described.

The door coupling 1′ also has the advantage that the hinge part 9 a′ canbe fastened in a frontal region of the door pillar 3 and, in particular,to a surface of the door pillar 3 facing to the side, this region beingcovered by a projecting part of the door 2, with the result that theweight load of the door 2, which is usually of a large design in thecase of four-joint couplings, and therefore the deflection of said doorand the moments resulting therefrom predominantly form a load on thesupporting arm 4, which is of solid design in the manner of a stiffplate body. The vibration or jamming, known from four-joint hinges, ofthe door coupling due to dynamic stresses on the coupling 1′ in the caseof heavy doors is thereby prevented, and the smoothness of running ofthe coupling 1′ is thereby influenced positively.

The invention has been explained in greater detail above with referenceto two preferred exemplary embodiments, it being possible for furtherrefinements of the control rod, for example as a divided control rod,likewise to be realized in order to improve the adjustability of theposition of the door in the corresponding recess of the vehicle bodywith simultaneous ability to pivot around the z-axis of the vehicle.

What is claimed is:
 1. A door coupling for a door of a vehicle, in whichthe door can be displaced with respect to a door pillar in a transversemovement combined with a pivoting movement by means of a four-jointmechanism, the four-joint mechanism comprising a supporting armconnected in an articulated manner to the door and in an articulatedmanner to the door pillar, the four-joint mechanism comprising a controlrod connected in an articulated manner to the door and in an articulatedmanner to the door pillar, wherein the supporting arm is fastened in anarticulated manner with regard to the door and pillar at, in each case,two gudgeons assigned to the end regions of the supporting arm, whereinthe supporting arm comprises a base supporting arm, at least onesupporting arm part which can be detached from said base supporting arm,and at least one fixing device for the mutual fastening of the basesupporting arm and supporting arm part, wherein said at least onesupporting arm part comprises the two gudgeons provided at one end ofthe supporting arm, wherein said base supporting arm and said supportingarm part define a tangent plane, and wherein the fixing device passingthrough the tangent plane allows adjustment of the supporting arm partwith respect to the base supporting arm by mutual twisting around apivot axis which is substantially perpendicular with respect to thetangent plane.
 2. The door coupling according to claim 1, wherein thepivot axis is arranged between the gudgeons of the supporting arm part,and at a distance from the pivot axis at least one fixing and guideelement passes through the tangent plane of the base supporting arm andsupporting arm part.
 3. The door coupling according to claim 2, whereinthe fixing and guide element at least comprises a slot which is formedalong a circular arc around the pivot axis in one of the base supportingarm and of the supporting arm part and a hole which is arranged on thecorresponding circular arc in the side of the respectively other part ofthe base supporting arm and supporting arm part, the supporting arm partbeing releasably fixable in each rotational position with respect to thebase supporting arm by means of at least two spaced-apart fixingelements, on the one hand in the pivot axis and on the other hand on acircular arc at a distance thereto.
 4. The door coupling according toclaim 2, wherein the fixing and guide element comprises a screw and nutelement.
 5. The door coupling according to claim 1, wherein the controlrod is of single piece design and, with regard to one of the door andpillar, is coupled to a bearing plate to which a corresponding gudgeonof the supporting arm is also coupled, and wherein the control rod, atits end remote from this side, is coupled to a hinge part which can befastened in a manner enabling it to be displaced jointly with and in thedirection of the control rod relative to a corresponding hinge partassigned to a gudgeon of the supporting arm.
 6. The door couplingaccording to claim 5, wherein the hinge part which is assigned to theremote end of the control rod can be displaced relative to thecorresponding hinge part of the supporting arm by a slot being formed inat least one of the two hinge parts.
 7. The door coupling according toclaim 1, wherein the control rod is fastened to the door and to the doorpillar via a respective hinge part outside the supporting arm.
 8. Thedoor coupling according to claim 1, wherein the control rod is oftwo-piece design, and the two parts have means for releasably fixing inplace a changeable length of the control rod.
 9. The door couplingaccording to of claim 1, wherein the at least one supporting arm partfaces the door.
 10. The door coupling according to claim 1, wherein theaxis passing through the tangent plane is the axis of a screw andcoincides with the pivot axis.
 11. The door coupling according to claim1, wherein, with the door closed, the pivot axis lies substantiallyhorizontally and parallel to the direction of travel of the motorvehicle.